Battery Charging?

Hello, So I have a 9.6 volt  NI-CD 4 hour quick charger and the battery(600mah) that goes with it, but I was wondering if I could charge a 7.2 volt 2000mah, Ni-Mh battery with it. If i can for how long?

Topic by ben2000   |  last reply

Battery Charging? Answered

If i charge a battery when it's half full will ruin the battery life between charges?

Question by KnexFreak360   |  last reply

battery charging?

How can i charge my battery, i've lost my charger. the battery is 14.4V 1.5Ah Li-ion

Question by johnnywgk 

Battery Charging? Answered

Hello, So I have a 9.6 volt  NI-CD 4 hour quick charger and the battery(600mah) that goes with it, but I was wondering if I could charge a 7.2 volt 2000mah, Ni-Mh battery with it. If i can for how long?

Question by ben2000   |  last reply

charge battery

I have battery 1cell NI-MH AA 1.2 v 1500mAH   and i need to charge it by using smps and diode for detect peak voltage of battery   i prefer fast charge for maximum 2 hours for my project  how much voltage and current i need in output of smps ?

Question by omar kotrash    |  last reply


I have a Gateway Laptop..meant to run on 98 but i installed Windows ME on runs fine...its just that the Battery won't Charge anymore....any help???

Question by KountKurisu   |  last reply

Induction Charging ? Answered

OK, I have disassembled a old electric tooth brush and I am trying to reduce the size and one of the things I have deemed unnecessary is the PCB that runs the timer built into the toothbrush. However, one thing I am wary of at this moment is that the toothbrush is a induction Charger which is a A/C and I don't know if I can just remove the board and be OK or do I need to rectify the current into D/C to continue charging the battery. If the latter is the case what do I need to achieve this?

Question by Jayccob   |  last reply

SLA Battery Charging? Answered

Quick question about charging SLA Batteries, I haven't really dealt with battery charging too much in the past.  I have two 12v 5Ah SLA batteries, in series, and I have built an under/over voltage protection circuit for each of them, but while charging I noticed that testing voltages across each battery, they are different, however, as soon as I remove the charger and test them as is, they have the exact same voltage (+/-0.05 volts, they are very close).  Is this just because the charger is hooked up, or should I be worried at all about that? I am charging them to 14.75 volts each, or would like to, they say they should be charged to 14.5 to 15v right on the front of them.  While charging they both climb, but one climbs faster and stops once the voltmeter reads 15.2v across it.  0.2v over the rated value really doesn't seem to be of major concern, I just find it odd the different voltmeter readings across the batteries are different while the charger is connected and identical when its not.  Does it have something to do with charging them in series?  I did read that you really can't measure batteries while charging, you have to disconnect the charger first, but any insight would be appreciated.

Question by Electric Spectre1   |  last reply

12v battery charging?

I'm making a prop that has 6 12v 6800mAh rechargeable batteries, but i wanted two ways of charging them, a normal plug in to a wall adapter, but also jump lead connectors, so I'm able to charge it of a reving car, or a leisure battery, all my questions are, is what would i need in the circuit to make it safe, and work, imbetween the jump lead charge wires, the normal adapter charger lead, and the batteries them selfs. JUMP LEAD------------  ??  ----------------------------       WIRES                                                          |                                                                             |------------------  ?? -------- BATTERIES ----------12v -------                                                                             |                                                                             POWER ADAPTER------------------  ??  ------------|                       

Question by infinity1   |  last reply

charging batteries with 240V? Answered

I was thinking, wall transformers only transform so much energy(70-90%?) the rest goes off into heat. so, wouldnt it be better to charge 160 AA batteries at the same time in serial (thus making 240V) directly off the wart? i know this is just theory, since its not practical, not managable or anything, but i just wondered if it could be done. would this solve the energy loss from heating the transformator up?

Question by godofal   |  last reply

laptop battery? Answered

I have a dell laptop which does not seem to charge when I try to charge it with the power lead. At the bottom of my screen it says 'plugged in, not charging'. What can I do to make it to charge? The power supply always overheats and gets in my way.

Question by knektek   |  last reply

Charging Circuit

I was wondering if anyone had any ideas on how to make a circuit so that I could charge a battery, but that I can also power an amplifier when the battery is not charging. Currently I have a switch that switches between a charging circuit and powering the amplifier, but I was looking for a way to do this without having a switch that I have to control

Topic by Fozzibehr   |  last reply

Zapped a battery.?

And still wont charge, it's a 36v Ni-Cd. it has 10 separate cell inside the plastic holder, which i took apart and zapped individually then soldered back together. i did not try to charge it for 1 week after zapping, should i have charged it immediately. Or any other ideas

Question by johnnywgk   |  last reply

Solar charging

Hi, pls suggest me for the following A 20Watt ( 20V , 1000 ma) solar panel is connected to charge a 12V, 80AH battery . What is the value and wattage of a Current limiting resistor to be added?

Topic by khhrao   |  last reply

Capacitor Charging?

How do I charge a capacitor rated for 450v at 1150uf using 2 AAA batteries? I tried using a mini transformer but it takes a very long time. Is there a quicker solution? Thanks in advance, IndianHacker

Question by IndianHacker002   |  last reply

MP3 Battery won't charge?

I have just bought a generic MP 3/4 and did not fully charge the battery before exploring it's apps. Now I have a half full battery that won't charge any further. Can anyone help?

Question by willywombat   |  last reply

how not to over charge a battery?

I want to connect my waterwheel to a car battery, but I dont want it to get overcharged and blow up! what can I do?

Question by tim13211   |  last reply

charge a battery while using it?

Https:// hi, i'm looking for a way to charge a 12v deep cycle lead acid battery while powering an amplifier from the battery. Can i literally just attach the battery charger to the battery as well as the amplifier as long as the connections to the amplifier and charger do not touch? or is it not that simple?  The instructable linked above is what i what to implement it into. Any help will be appreciated! 

Question by WillERoberts   |  last reply

charging 10s5p battery pack

I'm working on an ebike conversion. I'm buying laptop batteries to take out the 18650s and put them in my pack. I'm looking at a 10s 37v pcm. If I make it in 10 sets of 6 to get 37v 14.4ah, then how can I safely charge the battery so that they don't charge unevenly in each set?

Topic by leaf26   |  last reply

Charge battery with bike dynamo

Hello, I would like to charge a battery using my dynamo on my bike. The battery I would like to use for my head and tail light for example and for charging my phone. Would this be possible and how? Thanks in advance

Topic by doppiej   |  last reply

Charge batteries with a bike dynamo? Answered

I am experimenting with ways to charge batteries while cycling. Standard bike dynamos produce 3 watt 6 volts.  That's not a lot of power but 12 hours of cycling should charge a 36 watt hour battery.  I am thinking about about making my own battery pack.  It needs to be 4s1p 14.4 volts.   What I need help on is what sort of battery chemistry to get: lithium ion, LiMiNi, lithium poly, etc.  The batteries I need should charge efficiently at low current (about .25 amps).   The other thing I need help with is how to turn the dynamo power into charging power.  I know I need to rectify it and smooth it.  I have heard about Zener diodes.  They are used in solar applications because they are more energy efficient.  Should I use those? Lastly, dynamo power varies depending on the speed of the bike (Between 0 volts and 12 volts.)  Lithium ion cells need a 4.35 volt charge.  Would it be better to use a regular voltage regulator you get a radio shack or a switching voltage regulator.  I have an anyvolt 3.  Maybe there are PCBs you know of which automatically regulate a vacillating input voltage. 

Question by Noblenutria   |  last reply

charge controller

I have the cm3024z charge controller. i have 240 watts going in, controller going to batteries, no conection on the load,   have 1500 watt converter hooked to batteries. set the controller as such,,, HvD-14v, LvR-12.5 v'  LvD-10.8 v . my voltage comming in to the controller is good, when i get to the hvd it kicks out at 14v as it should, but my lvr doesnt want to kick back in. i have let the batteties drain below the lvr but will not kick back in ..  is there anybody that can help with this, i have retured the first one and this is my second one with same problem. i have left the system hooked up as acording to manual,but after it kicks out it just wont kick bavk in unless i disconnect the panels and reconnect them.   all help would be appreciate, thanks

Topic by puddlepod   |  last reply

Strange battery charging idea.

So I have an Idea for a charger for a portable computer.  It will be solar powered, and charge li-ion batteries.  My question is how could I simultaneously charge batteries and power the computer at the same time.  No schematics are needed, just a quick written answer. Thanks!

Topic by Skiboy941   |  last reply

Charging multiple 12v batteries

I have eight 12v 18Ah SLA batteries that I need to wire to get 48v. I need to be able to charge them all at once, but can't find a 48v charger anywhere. Is there a way I can wire a 12v charger to parallel charge the batteries while they're wired in series?

Question by Charlie_Szasz   |  last reply

Solar charging a battery with Arduino?

I am making a solar rover robot using an arduino duemilanove. I have a 12 volt solar panel and a 9.6 volt nicad battery. I am wondering if this circuit I sketched would allow me to prevent the battery from over charging. The battery is monitored by dividing the voltage and connecting it to analogue input on the arduino. When the battery is fully charged, the arduino sets an output pin HIGH and breaks the connection between the panel and the battery using a PNP transistor. Does the transistor subtract current from the circuit? In the open state will there be more than 9.6 volts entering the battery? here are some links to the robot so far! (without solar installed) Pics! http:// Video!

Question by Revolt Lab 

battery with easy charging method? Answered

I am looking for the best way to implement a battery supply for my project. It needs to be able to fit in an enclosure measuring 5 x 2.5 x 2 inches. It needs to have a voltage in the range of 7 to 12 volts and have a fair amount of capacity. (maybe around 1500 - 5000 mAh?) The battery(s) also should be easy to charge, such as through a regulated voltage supply, with no complex control circuitry. It can be multiple batteries. I am mainly looking for the best type of battery here. (NiMH, SLA, Lithium, etc.) Any suggestions?

Question by brady911   |  last reply

Car Alternator Battery Charging

Here is an alternator. 75 amp 12 volts. But i m not sure how to connect the 3 wires.. what i know is that screw in black plastic case is battery +ve and alternator body is battery -ve, Please guide me how to use other 3 wires ( green black and yellow). Thankx in advance ;)

Topic by SyedA58   |  last reply

Battery Charging Light Circuit

Dear All I am building a small scale PV system and I want to implement a circuit that will allow a LED to light up when the battery is being charged from the PV cells Currently I have a general purpose PNP transistor with a 2KOhm resistor for the base and a 1KOhm resistor in series with the LED, however when running this simulation the LED will not light, even when I lower the values of the resistors Any help would be much appreciated 

Topic by EmptyCoffin92   |  last reply

Wind turbine to charge batteries

I have a solar electric system with a battery back up for power outages.(it is also grid tie) I would like to add a wind turbine to charge the batteries in extended outages with no sun and hopefully wind ( we normally have low wind but storm outages have lots of wind). The batteries are 12 volt connected in series to produce 48 volt. Can I, should I, get a 48 volt turbine and connect direct to the batteries or some other voltage and go through the inverter like the solar panels do and if so how and what voltage turbine?.. Chris

Question by papabear911   |  last reply

Can this Charger charge this battery?

For the past couple days I have been looking through the internet for the perfect battery and charger for very little and i think I found it!!! Please let me know if you think this battery and the charger will be compatible and will charge properly. I intend on cutting the leads of so I can have matching leads  (so the battery and the charger can connect obviously) Here is the battery I intend on purchasing:;=item3f19342b8d Here is the charger I intend on purchasing to charge the battery:;=item3363a9d51d Please let me know if this charger will be able to charge the battery! Thank you so much for all your guys help! I love instructables, everyone helps everyone out!

Question by jnajmy   |  last reply

What is the optimum charging voltage for 1.2 volt ni-cad rechargeable AA batteries? Answered

I am going to build a solar panel that charges these batteries so i I need to know the best voltage to charge them.

Question by airsofter1   |  last reply

How to re-charge Duracell 21/23 Batteries?

Can a dead(drained) Duracell 21/23 battery be re-charged with-out it exploding in your face?

Question by Tonester   |  last reply

trickle charger for 14AH battery?

Hi, i am looking into making a 12v UPS for my home cctv system. i have two 12v 7AH batterys like the type used in fire and burglar alarm panels. my aim is to have a 240v input which gets converted to 12vdc and powers my dvr and cameras. the power supply of the dvr alone is 5 amps so i would need 1 5 amp output and then 16 lower amp outputs for the cameras but i guess this could just be done with fuses. now, here is the tricky part: in whilst also powering the dvr and cameras, i also need it to charge my two battery's wired in parallel so theres 14 ah of 12v battery's to charge (i may also add more at a later date). in the event of a power loss, a relay or some other switching device will switch power to all the devices to the battery so that its backed up. the only problem is that i am new to battery charging and don't fancy blowing them up. schematics, help suggestions all greatly appreciated. thank-you. - Luke

Question by ljarrald   |  last reply

Batteries and charger? Answered

So I got one of those one cell battery bank that come also with a little crank generator. So far I took both of these apart to make one into a 2cell. So now these batteries are a parallel, my ? is if the voltage stays the same with the charging board and the mah is double this should not effect the board correct? and or the batteries. So far its been working both batteries reads the same voltage so the charging board must work. Now hear is the thing that I am concerned with, if I was to add 6 more into a parallel then all batteries would be the same MAH right. This should not damaged the board?

Question by dominick.j.pezza   |  last reply

Charging BoostCaps

I recently got a few of the 3000 farad 2.7 boost caps from electronic goldmine.  I have a quick question about charging them.  Applying a higher than rated voltage before the capacitor is charged all the way would be fine, right?  The voltage drop should cause the source voltage to approach 0, thusly below the 2.7 volt rating.  As an extreme example, lets say you simply hooked up a 9 volt battery to it.  Since the battery can only supply like 200mA, the voltage drops to nearly 0 as the capacitor appears to be a dead short.  The dielectric (or ion exchange or napheon membrane or whatever it is in a ultracap, lol) should be fine, correct? My main goal is to later hook up one or two of these for a regenerative brake system of something like a small gokart or bike or something.  Stopping at 30mph is like (assuming 200kg total mass) 20k joules, and each one can hold about 10k joules, and assuming a max efficiency of like 30 or 40% (I think itd be much lower, though), these capacitors could brake a gokart going fairly several times without having to be discharged inbetween cycled (but of course they would be).  For braking, could these essentially be hooked up directly (of course with pwm, and other things, but in essence:) to the motor with a little protection circuitry to prevent overcharging the capacitors?  Or would the higher voltage instantly puncture and destroy the boostcap?

Topic by guyfrom7up   |  last reply

Li-ion battery charging question

I'm new here so hi first. Now to the question I've been making a portable wii lately and I've gone quite far, but I'm stuck at the power. So I've got two 20000mAh mobile batteries (10000mAh 4.2V x2 in parallel for one mobile pack) i was planning to connect the batteries in series to get the required 12v+ power to get the Wii running . Since this is a mobile battery it has a charging circuit for the battery in parallel . I was thinking how to charge the batteries in balance (in series) . It's quite confusing ,any help will be appreciated!( There is very little information of the batteries inside the pack, it only says [10000mAh Max 4.2V])

Question by WanjiangW   |  last reply

Laptop battery loosing performance?

I jut got my new laptop. My questions is how do i prevent my battery from loosing performance? I know that my battery wont stay at the same performance level for a long time, but i would like to slow the proces down. I take my laptop to school mon-fri. one thing i do is to unplug the power source when the battery is fully charged (otherwise i think it damages the battery), and recharges the battery when power is low. Are there other ways to treat the battery so it doesn't loses performance as fast? What do you do/think?

Question by bjarkethomsen   |  last reply

Charging Multiple NiMH

I'm modding something (secret, Instructable later) and there's going to be some integrated NiMH batteries to replace the one 1.5 AA battery that the device use to use. Due to funky space constrictions, I'll be using 7 tiny 320mAh 1.2V NiMH coin cells in parallel (to get a decent amount of maH). How hard is it to charge a bunch of batteries like this? Could I get a chip from a place like Maxim or TI? All of their chips require the batteries to be in series... Thankyou!

Topic by guyfrom7up   |  last reply

battery problem?

 hello, i have helecopter and i wanna add some device that make battery gives same current depend on throtle for any voltage, i have problem  the problem is that when battery is full charge the throtle differ than when its not fully chge i want it to be same all time , current mirror works here i wont to burn the helicopter?are  

Question by britich   |  last reply

Solar power & battery? Answered

Hi everyone, I would like like to power a circuit that requires 6v from a battery charged by a solar cell. Could someone recommend a battery & cell specs? Would like the circuit to run at night for at least 3 hours. Battery needs to be quite small. I've picked Powerfilm solar cells, just need to know what voltage & amperage to use for a small 6v rechargeable battery. Thanks! 

Question by BlondeJamesDean   |  last reply

Motorola Bluetooth charger to charge 3.7v li-ion batteries Answered

I have a little bluetooth charger that outputs 5.0V and 550mA, am I able to charge 3.7v li-ion batteries with this?

Question by vallka   |  last reply

I cannot seem to charge my run battery at the same time i am using an inverter .

I am trying an experiment to charge a run battery supplying power to an inverter that is used to  make more DC voltage. I Can charge an alternate battery, but when i connected to the run battery it drains to fast  and the inverter stops working. I have a diode on the positive so no drain there. How Can i allow charge voltage in at the same time as running an inverter?

Question by thomasskelly8   |  last reply

Get battery charge level in Linux

I have a small all-in-one motherboard that runs Linux ( It only needs 18V to power up and the battery from my Black and Decker drill is 18V. I am able to get the board  to power on by holding some wires on the leads of the battery. My question is, can Linux detect how much charge is left through a DC jack? Or would that take some extra circuitry? My goal is for the user to see a percentage of battery life left (like on a laptop) and maybe to shut the board down if the charge gets too low. Any advice is appreciated.

Topic by bwallen   |  last reply

batery charging

Having had to buy a dedicated charger for some 18650 cells (at my wife's insistence) I took an interest in these cells for the first time and their smaller cousins the 123a. At with maximum capacities I've come across so far of 3700mAh and 2000mAh respectivley that's twice the capacity of the battery in my smart phone and 2.5 times the capacity of the one in my basic bar phone. The smart phone width would accommodate 3 of the 18650 cells (6 days without charging at my rate of use) and the bar phone possibly 4 of the 123a's (70 hours talk time or 10 months on standby). Yes this would mean a custom made back, but there is at least one instructable on molding a GRP/ carbon phone back adjusting it to take extra cells and maybe ports just needs modeling clay. I suppose I could just carry a power bank, but why if the phone can be its own power bank? Removing the guts of a power bank and building a new phone back to accommodate them may be the simplest answer to this but, my questions are:- A) I've got old mobiles laying around could I use their charging circuits to charge these standard Li-ion cells? Assuming that is a yes that would mean a long charge every 6 days/ 10 months. I gather there are problems associated with parallel charging/ discharging of Li-ion cells and over discharging so, B) Any advice on doing this other than don't? On the assumption that's a don't or even if its not this strikes me as a safer possibility. C) Could a micro controller be configured to discharge one cell to its limit then switch to the next full cell. D) Could a micro controller be configured to charge one cell to capacity then look for the next under capacity cell and charge that. E) if so could it do both at the same time? If A is possible and the rest not then a multi position switch is  probably the answer.

Topic by Stan1y   |  last reply

is there a way to charge a cell phone battery without the cell phone. If so, how?

The reason i ask this question is because my cell phone stopped charging my battery. it's not the charger or the where u plug the charger into the cell phone that is not making contact.   I know that regular batteries (AAA, AA) can be charged universally as long as the battery is a rechargeable one.  How about a cell phone battery?

Question by johnshericosmo   |  last reply

I need to prevent a battery from discharge?

I want to connect an air pump (5-12v) to a car battery. that battery is also connected to a solar charger panel (seen on other instructables). What i need its a circuit where i can monitor the batterry (a 12v cuttoff) so that when it goes below charge, it turns off the air pump, letting it to freely charge and start again. i thought of a NE555 or a relay. appreciate any help.

Question by pchalita   |  last reply

Mimicking a 3.7v lithium battery with solar power

I'm trying to replace a digital cameras' battery with a solar power source instead. The camera would only work in the sun with this power source, but that's exactly what i want. The battery I'm trying to mimic is 3.7v at 760 mA. I was thinking of making a solar panel with an output of 5v at 1amp, and then using a voltage reg to bring the 5v down to a steady 3.7v. Can I get a 3.7v regulator? Is there such a thing as an adjustable/customizable voltage regulator? Would 4v be fine instead of 3.7v? is it close enough?

Question by solarbug   |  last reply

LiPoly charging question?

Hi Everyone, I am creating a 6 cell pack (first time as you can tell) of LiPoly batteries 14.8V 5A it will have 3 groups in series of 2 in parallel for a 44.4V 10A pack. In order to properly charge and maintain the batteries does anyone have any recommendations for a good balance charger from hobbyking or elsewhere? Also in order to properly charge them should I charge each of the 6 cells individually, or charge the 3 packs of 2 in parallel using these?  Thanks for your help.

Question by Hammock Boy   |  last reply

How to charge a capacitor? Answered

I read some where that you need a rising amount of volts to charge a capacitor, but I also always see around that you can just charge a capacitor on just a straight battery that is DC. I am very confused how you can and should charge a capacitor.I think the formula for charging a capacitor is i=C(dV/dT)Thanks

Question by squirt8500   |  last reply